Benzodiazepine Derivatives as Corrosion Inhibitors of Carbon Steel in HCl Media: Electrochemical and Theoretical Studies

Protection of Metals and Physical Chemistry of Surfaces - New benzodiazepine derivatives, namely 8-Chloro-1,2,3,4,10,11-hyxahydrospiro[cyclohexane-1,11-dibenzo[1,4]diazipine] and...     

Synthesis of Novel Tetra(µ3-Methoxo) Bridged with [Cu(II)-O-Cd(II)] Double-Open-Cubane Cluster: XRD/HSA-Interactions,Spectral and Oxidizing Properties

A new double-open-cubane core Cd(II)-O-Cu(II) bimetallic ligand mixed cluster of type [Cl₂Cu₄Cd₂(NNO)₆(NN)₂(NO₃)₂].CH₃CN was made available in EtOH/CH₃CN solution. The 1-hydroxymethyl-3,5-dimethylpyrazole (NNOH) and 3,5-dimethylpyrazole (NNH) act as N,O-polydentate anion ligands in coordinating the Cu(II) and Cd(II) centers. The structure of the cluster in the solid state was proved by XRD study and confirmed in the liquid state by UV-vis analysis. The XRD result supported the construction of two octahedral and one square pyramid geometries types around the four Cu(II) centers and only octahedral geometry around Cd(II) two centers. Interestingly, NNOH ligand acts as a tetra-µ³-oxo and tri-µ²-oxo ligand; meanwhile, the N-N in NNH acts as classical bidentate anion/neutral ligands. The interactions in the lattice were detected experimentally by the XRD-packing result and computed via Hirschfeld surface analysis (HSA). The UV-vis., FT-IR and Energy Dispersive X-ray (EDX), supported the desired double-open cubane cluster composition. The oxidation potential of the desired cluster was evaluated using a 3,5-DTB-catechol 3,5-DTB-quinone as a catecholase model reaction.     

One Step Synthesis of NiO Nanoparticles via Solid-State Thermal Decomposition at Low-Temperature of Novel Aqua(2,9-dimethyl-1,10-phenanthroline)NiCl2 Complex

[NiCl₂(C₁₄H₁₂N₂)(H₂O)] complex has been synthesized from nickel chloride hexahydrate (NiCl₂·6H₂O) and 2,9-dimethyl-1,10-phenanthroline (dmphen) as N,N-bidentate ligand. The synthesized complex was characterized by elemental analysis, infrared (IR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy and differential thermal/thermogravimetric analysis (TG/DTA). The complex was further confirmed by single crystal X-ray diffraction (XRD) as triclinic with space group P-1. The desired complex, subjected to thermal decomposition at low temperature of 400 ºC in an open atmosphere, revealed a novel and facile synthesis of pure NiO nanoparticles with uniform spherical particle; the structure of the NiO nanoparticles product was elucidated on the basis of Fourier transform infrared (FT-IR), UV-vis spectroscopy, TG/DTA, XRD, scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDXS) and transmission electron microscopy (TEM).     

Model Free Approach for Non-Isothermal Decomposition of Un-Irradiated and γ-Irradiated Silver Acetate: New Route for Synthesis of Ag(2)O Nanoparticles

Kinetic studies for the non-isothermal decomposition of unirradiated and γ-irradiated silver acetate with 10(3) kGy total γ-ray doses were carried out in air. The results showed that the decomposition proceeds in one major step in the temperature range of (180-270 °C) with the formation of Ag(2)O as solid residue. The non-isothermal data for un-irradiated and γ-irradiated silver acetate were analyzed using Flynn-Wall-Ozawa (FWO) and nonlinear Vyazovkin (VYZ) iso-conversional methods. These free models on the investigated data showed a systematic dependence of Ea on α indicating a simple decomposition process. No significant changes in the thermal decomposition behavior of silver acetate were recorded as a result of γ-irradiation. Calcinations of γ-irradiated silver acetate (CH(3)COOAg) at 200 °C for 2 hours only led to the formation of pure Ag(2)O mono-dispersed nanoparticles. X-ray diffraction, FTIR and SEM techniques were employed for characterization of the synthesized nanoparticles.     

Synthesis,characterization and magnetic properties of Mg2+ doped green pigment Cobalt aluminate nanoparticles

Journal of Materials Science: Materials in Electronics - The green pigment cobalt aluminate nanoparticles have been prepared by the simple and cost-effective co-precipitation method. And also, the...     

Synthesis and Characterization of Hybrid Materials Consisting of n-octadecyltriethoxysilane by Using n-Hexadecylamine as Surfactant and Q(0) and T(0) Cross-Linkers

Novel hybrid xerogel materials were synthesized by a sol-gel procedure. n-octadecyltriethoxysilane was co-condensed with and without different cross-linkers using Q(0) and T(0) mono-functionalized organosilanes in the presence of n-hexadecylamine with different hydroxyl silica functional groups at the surface. These polymer networks have shown new properties, for example, a high degree of cross-linking and hydrolysis. Two different synthesis steps were carried out: simple self-assembly followed by sol-gel transition and precipitation of homogenous sols. Due to the lack of solubility of these materials, the compositions of the new materials were determined by infrared spectroscopy, (13)C and (29)Si CP/MAS NMR spectroscopy and scanning electron microscopy.     

Corrosion inhibition performance of 4-(prop-2-ynyl)- [1,4]-benzothiazin-3-one against mild steel in 1 M HCl solution: Experimental and theoretical studies

4-(prop-2-ynyl)-2H [1,4]-benzothiazin-3(4H)-one (PBO) was synthesized and evaluated on corrosion resistance for mild steel (MS) in1 M HCl environment. The molecular and crystal structure of PBO has been determined by single-crystal X-ray crystallography, Hirshfeld surface (HS) analysis was carried out by using Crystal Explorer 17.5. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PDP) techniques were used to find corrosion rate (CR) and corrosion inhibition efficiency (η) in the presence and absence of PBO. These techniques were supported with energy dispersive X-ray (EDX) and scanning electron microscope (SEM). Molecular Dynamics Simulation (MDS) and Frontier Molecular Orbital (FMO) are realized by means of the Density Functional Theory (DFT) method. The results show that PBO could offer an inhibition efficiency of 92% at 303 K. The type of inhibition mechanism of PBO was mixed-type. The Langmuir isotherm proved the highest compliance with experimental data, representing the generation of protective mono-layer of inhibitors on the MS substrate. The SEM pictures displayed a metallic substrate covered with a highly compact protective layer covered. The theoretical findings suggested by electronic/atomic computer simulations supported the inhibitive chemicals interfacial adsorption through reactive centres.     

Aminothiazolyl coumarin derivatives as effectual inhibitors to alleviate corrosion on mild steel in 0.5 M H2SO4

To diminish corrosion which leads to structural damages and to implement a green mitigator has induced the usage of aminothiazolyl coumarin derivatives to study mild steel (MS) corrosion using potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), weight loss, atomic force microscopy (AFM), and electron microscopy with energy dispersive spectroscopy (SEM–EDS) spectrometry in acid medium. The results showed that the inhibition efficiency was 90.8% for the least effective inhibitor and 97.1% for the most effective inhibitor at optimal concentration (10 mM). Enhancement of inhibition efficiency in weight loss method and increase in R_p values in impedance and mixed nature of the inhibition in polarization measurement reveals the best inhibition capacity of coumarins over the MS. The coumarins were characterized using FT-IR, NMR and Mass spectroscopy. The adsorption was well fitted with the Langmuir adsorption isotherm model. SEM–EDS and AFM images confirmed the shielding effect of coumarin derivatives through a layer formation on MS against acid medium. The adsorption mechanism of aminothiazolyl coumarin derivatives was further explored by quantum chemical calculations (DFT) and molecular dynamics (MD).

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Effect of Bi3+ doping on the properties of chemically deposited GdS films

CdS films were prepared by a chemical bath deposition technique with different Bi concentrations (0.01 to 5 wt %) on glass substrates. Optical and electrical properties were studied with these films. It was observed that the absorption coefficient of the CdS film increases with Bi-doping up to 2 wt % and then decreases. These results are explained in terms of the crystallanity of the film. The optical band gaps (E_g) were determined and found to decrease with Bi-doping. The conductivity and thermoelectric power are higher for doped films than undoped CdS films. These results are explained by considering the existance of Cd²⁺ ions as donor centres in Bi-doped CdS films.